Robot loading and machining of object-of-revolution workpieces, under numeric control, has long been feasible. However, alignment of the workpiece centerline with the centerline of the machine tool has heretofore been a manual operation requiring accuracy and a time expenditure.
The art has numerous alignment devices and robotic end effectors. For example U.S. Pat. No. 5,312,220, issued to Torrii, et al., on May 17, 1994, discloses an industrial robot for attaching and removing a work piece from a machine tool. U.S. Pat. No. 5,321,353, issued to Furness, on Jun. 14, 1994, discloses an optical system and method for precisely positioning a robotic tool. U.S. Pat. No. 5,451,850, issued to Karakama, on Sep. 19, 1995, discloses a method of correcting a position of a tool center point. U.S. Pat. No. 5,457,367, issued to Thorne, on Oct. 10, 1995, discloses a tool center point calibration apparatus and method for accurately determining appropriate tool center points for a robot to allow for proper tool alignment and correction of robot programs. U.S. Pat. No. 4,776,749, issued to Wanzenburg, et al., on Oct. 11, 1988, discloses a robotic device which a has a support structure and tool implement holding member which is positional within three dimensional space of the support structure. U.S. Pat. No. 4,802,816, issued to Mezhinsky, on Feb. 7, 1989, discloses a pick and place machine that has two pairs of centering jaws slidably mounted in rectilinear slots of a shift plate. U.S. Pat. No. 4,820,113, issued to Farquhar, on Apr. 11, 1989, discloses a part manipulating head for attachment to a robot. U.S. Pat. No. 4,929,009, issued to Vandersluis et al., on May 29, 1990, discloses an end effector for forming part of the relocatable space station remote manipulator system. U.S. Pat. No. 5,074,741, issued to Johansson, on Dec. 24, 1991, discloses a manipulator intended for cooperation with an industrial robot. for positioning a workpiece with respect to the robot. Finally, U.S. Pat. No. 5,243,264, issued to Takada et al., on Sep. 7, 1993, discloses a tool fastening apparatus for industrial robots.
What has been missing from the art is a device that will facilitate the automated, or robot, loading of a workpiece onto a machine tool without requiring great accuracy of the robot or manual alignment.
Accordingly, it is an object of the present invention to provide a device for mechanizing the alignment of the centerline of an object-of-revolution workpiece with the centerline of a machine tool upon which the workpiece is mounted.
Another object of the present invention is to provide such a device that is adapted for rigid attachment to various standard spindle designs.
Other objects and advantages over the prior art will become apparent to those skilled in the art upon reading the detailed description together with the drawings as described as follows.